OP ARTS AND SCIENCES. 



303 



The substance dissolved in concentrated sulphuric acid and warmed, 

 gives a dark bluish green coloration which is very characteristic. It 

 is difficultly soluble in most organic solvents except chloroform. By 

 passing chlorine into a chloroform solution of the substance it forms 

 a pale yellow oily addition product, which, on treating with zinc dust 

 and acetic acid, is converted back to the original substance. Alcoholic 

 potash saponifies it to the corresponding dibasic acid, — 



p-Dichlorhenzo-p-difurfuran a-dimethyl ^-dicarboxylic Acid, 



CI O 



CO,H 



CO9H. 



The ethyl ether described above is easily saponified by heating with 

 twice the calculated amount of alcoholic potash. After driving off the 

 alcohol, taking up with water, and acidifying with dilute acetic acid, 

 the free acid separates out as a fine white powder, which, examined 

 under the microscope, consists of crystalline needles. It sublimes at 

 a higher temperature without melting, and is insoluble in organic sol- 

 vents and water. It was therefore dissolved in potassic carbonate, 

 precipitated by dilute acetic acid, and, after thorough washing with 

 hot water, dried at 130° and analyzed. 



0.2087 gram substance gave 0.3732 gram CO., and 0.0482 gram H2O. 

 0.2461 " 



Concentrated sulphuric acid gives a bluish green coloration similar 

 to that of the ether. 



The Addition Products of p-Dichlorquinonediacetoacetic Ether. 



As above mentioned, this substance is characterized by the ease with 

 which it forms addition products. Treated in chloroform solution 

 with one molecule of bromine, a complete absorption of bromine takes 

 place quickly without the slightest evolution of hydrobromic acid, and 

 a colorless odorless substance separates out in heavy scales, which melt 



